Immunocytochemical Localization of Collagenase in Human Skin and Fibroblasts in Monolayer Culture

Abstract

The development of a functionally monospecific antiserum to human skin collagenase has permitted the precise localization of this enzyme using fluorescence microscopy in tissue sections of human skin and in fibroblasts from primary cell culture. In human skin, collagenase is primarily localized to the upper or papillary dermis. Collagen fibers show pronounced staining suggesting that much of the enzyme present in skin is extracellular and perhaps bound to its collagen substrate. Cytoplasmic staining was also seen in fibroblast-like cells scattered in the upper dermis. Specific fluorescent staining was virtually absent in the mid-and lower dermis and in the epidermis. Fibroblasts obtained from human skin explants displayed a granular and frequently reticulated staining pattern primarily in the perinuclear region when examined either by immunofluorescent or immunoperoxidase techniques. By radioimmunoassay the culture medium contains material immunologically identical to skin collagenase. the findings suggest that the fibroblast is the major cell responsible for collagenase production.